1. Field of the Invention
The present invention relates generally to cover assemblies and more particularly, to a novel engine cover assembly for an internal combustion engine.
2. Description of the Related Art
Cover assemblies for internal combustion engines have been used for many years. Typically the engine cover assembly is made of metal and is clamped by means of metal bolts to the engine block. The metal cover assembly does not attenuate noise well or conform to the movement of the engine block relative to the engine cover. Some metal engine covers may increase the weight of the automotive vehicle. However, any replacement part must be of the same strength in order to function properly in the automotive vehicles. Many plastic covers have been tried but they have had shortcomings due to material creep strength and difficulties in staying securely fastened to the engine block. Plastic tends to have a high creep value which allows the bolt head to indent or make impressions into the plastic or the flange bow thus reducing the clamp load on the gasket sandwiched between the engine cover and the engine block.
Other types of covers have also been tried, for example a plastic cover has been formed to a metal type seal surface and then placed onto the engine head. However this type of cover does not allow any flexibility between the plastic and the metal. The plastic and metal seam becomes brittle which causes oil leaks. Thus, there has been a need in the art for a lightweight and high damping capacity engine cover for use in an internal combustion engine. The flange cover needs to have low creep characteristics so that it can be securely bolted to the engine block with no worry of creep.